/**
  * Add a new child model for given model.
  * If creation is successful, the browser will be redirected to the 'view' page.
  * @return mixed
  */
 public function actionAdd($parent_id)
 {
     $parent = $this->findModel($parent_id);
     $type = $parent->childType();
     $model = Competition::getNew($type);
     $model->parent_id = $parent_id;
     if ($model->load(Yii::$app->request->post()) && $model->save()) {
         return $this->redirect(['view', 'id' => $model->id]);
     } else {
         /** copy initial data from parent competition */
         foreach (['flight_size', 'registration_begin', 'registration_end', 'handicap_min', 'handicap_max', 'age_min', 'age_max', 'gender', 'recurrence_id', 'max_players', 'registration_special', 'flight_time', 'registration_time'] as $attribute) {
             $model->{$attribute} = $parent->{$attribute};
         }
         return $this->render('create', ['model' => $model]);
     }
 }